In November 2011, Kang sued South Korean comedian Choi Hyo-jong [ko] for "disrespecting the National Assembly" in a skit in Gag Concert.

[5] The lawsuit received widespread condemnation,[6] including from comedian Kim Won-hyo [ko], who protested against Kang's action on his Twitter account.

[7][failed verification] Kang was a frequent guest on several public TV shows including tvN's The Genius, and JTBC's Crime Scene.

On the reason for the ruling, Judge Park Dae-san said, "Kang Yong-seok, as a lawyer, forgot his status and basic duties and conspired with Kim Mi-na, who is in an affair, to forge a private document.

Kang, meanwhile, was put on trial on charges of forging documents to drop a lawsuit filed by the husband of famous blogger Dodomam Kim Mi-na, who allegedly had an affair with him.